1 Field of the Invention
The present invention relates to an instrument for application in endoscopic surgery.
2 Prior Art
An instrument which the wording of the introductory clause of Patent claim 1 starts out from is known from the German Patent De 43 24 254 C1.
That prior art reference discloses a surgical instrument for endoscopic operations which comprises a shaft. Three passages are provided in that shaft, which are disposed at the apices of an isosceles triangle. A pair of forceps or the like can be inserted into two of the passages, which present each a forceps jaw which can be pivoted. The third passage is provided for the insertion of an optical system.
The relative orientation of the forceps may be optional because the forceps may be inserted into the respective passage at any optional angle of rotation.
Even though the known surgical instrument can hence be adapted to almost any surgical operation for the performance of defined tasks which require precisely defined operating cycles, the expenditure for adjustment is very high:
In a number of endoscopic surgical operations it is necessary for instance, to xe2x80x9ccontractxe2x80x9d two tissue parts which are separated from each other, to maintain them in this condition, and to joint them subsequently, e.g. by a suturing or adhesive operation.
One example of such type of surgery is the operation on torn ligaments in a joint, such as the knee joint, or the in-vitro fertilisation of the fallopian tubes. Another example is described in the article by D. J. Tibbs et al., xe2x80x9cArterial Replacement with Minimal Interruption of Blood Flowxe2x80x9d, published in xe2x80x9cThe Lancetxe2x80x9d, 1958, pp. 292 to 294.
With the instrument known from the German Patent DE 43 24 254 C1 it is not possible to perform these operations because the pivoting axes of the elements of the forceps jaw and of the forceps jaw are disposed in parallel with each other. Hence the two bendable forceps, which are introduced independently of each other into a shaft with a plurality of passages, do not permit a coordinated movement in the sense of a selective approach of parts held by the two jaws of the forceps. Moreover, the individual passages are disposed at the apices of an isosceles triangle so that the manipulation of the contracted tissue part by means of an instrument introduced into the third passage is rendered more difficult.
With conventionalxe2x80x94separatexe2x80x94instruments such operations require not only much time but also a high degree of manual skill from the physician performing the operation because the latter is bound to handle several instruments, which are separately introduced into the human body, and to co-ordinate their movements.
The present invention is based on the problem of providing an instrument for application in endoscopic surgery which facilitates, for instance, the operations of xe2x80x9ccontractingxe2x80x9d two tissue parts separated from each other, maintaining the tissue parts in the contracted condition, and manipulating them subsequently, e. g. their joining by a suturing or adhesive operation. The inventive instrument is moreover intended to have a simple structure and to require only a slight expenditure in terms of preparation and adjustment.
The present invention starts out from an instrument for application in endoscopic surgery, which comprises a shaft including two forceps elements on its distal end, which are operable independently of each other by operating elements, with one of said forceps elements being pivotable about an axis at least approximately orthogonal on the longitudinal axis of the instrument and/or displaceable in a direction orthogonal on the longitudinal axis of the instruments, and which comprises at least one further passage.
In order to avoid incorrect operations the possibilities of manipulation are restricted on the inventive instruments for the movements of the forceps jaws as one unit:
In one embodiment merely one set of forceps jaw elements is pivotable whilst the other set of forceps element is not pivotable.
In the embodiment defined in claim 1 the other forceps element is pivotable about an axis which is not parallel with the pivoting axis of the first forceps element or displaceable in a direction orthogonal on the longitudinal axis of the instrument.
The inventive instrument so configured is suitable particularly for the performance of special tasks such as the contraction of tissue parts.
To this end it is preferable to design the pivotable part(s) of the jaw of each forceps element for pivoting about axes whereof each is arranged at least approximately in parallel with the connecting line between the seizing regions of the forceps elements. This orientation, which is opposite to the orientation between the forceps jaw and the pivoting axis as known from the German Patent DE 43 24 254 C1, permits the contraction even of sensitive tissue parts because the jaw parts, in the seizing operation, move approximately orthogonally on the direction in which the tissue parts are moved by pivoting the forceps elements.
When the distal exit aperture of a continuous passage is disposed between the jaws of the two forceps elements and when the continuous passage is so configured that a surgical instrument can be inserted (inter alia) into this passage, which instrument co-operates with the jaws of the two forceps elements, the following mode of operation is conceivable, for instance, for joining separate tissue parts:
The inventive instrument is introduced into the cavity where the tissue parts to be joined are located. The free ends of the tissue parts, i.e. the fallopian tubes, for instance, are seized with the jaw of one respective forceps element. Then the forceps jaw of one pair of forceps is moved in a direction orthogonal on the longitudinal axis of the instrument towards the other pair of forceps. With the two forceps elements of the instrument seizing the tissue parts, the first free end of one of the two tissue parts to be joined is moved towards the end of the other tissue parts. As soon as the free ends have reached a position in which it is possible to perform the joining operation the operating physician carries through the joining step. During the joining operation and possibly even after this step the parts to be joined are held with the inventive instrument.
It is, of course, possible, to use the inventive instrument also for other treating or processing operations in the human or animal body or in engineering applications.
It is moreover expedient to provide a pivoting operating element on the proximal end of the instrument for each pivotable forceps element, which when operated varies the pivoting angle and hence the spacing between the forceps elements in the direction of the transverse axis. The variation of the pivoting angle does not take any influence on the position of the jaw parts of this forceps element relative to each other. It is thus possible to move the free tissue parts to be joined towards each other precisely and without any damage to the tissue.
Furthermore an improvement is conceivable wherein the forceps elements are structured in the manner of known forceps or are known forceps, respectively, which are inserted into a shaft as a single unit. This configuration simplifies both the manufacture, the storage operations at the manufacturer, and the cleaning of the inventive instrument.
It is furthermore expedient to configure the shaft in the manner of a trocar or a laparoscope known per se. This trocar shaft may have an outside diameter of 10 mm to 13 mm, for instance when fallopian tubes are to be sutured.
It is moreover preferable to provide the elements for operating the jaw parts of the forceps in the form of handle partsxe2x80x94such as scissors handles, forceps handles or the likexe2x80x94which are biased into the position in which the respective forceps jaw is closed. This configuration has the advantage that the physician need not hold the jaw parts of the two forceps by holding the handles in a closed condition when contracting the tissue parts.
The spacing between the two forceps elements can fundamentally be varied in the most different ways. It is possible, for instance, to hold at least one forceps element on a resilient and outwardly bent mount. Then the forceps element is xe2x80x9cpressed inwardlyxe2x80x9d or the point of articulation is shifted, respectively, by means of a linear guide or a sleeve.
A particularly wide range of adjustment is achievedxe2x80x94specifically in view of the restricted diameter of endoscopesxe2x80x94including various possibilities of pivoting the distal end of the forceps elements or forceps, respectively, as a single unit:
The forceps jaws may be a component of flexible forceps known per se which have distal ends which are equally bendable in a manner known per se.
The pivoting or bending movement of the forceps jaws can be provoked in the most different ways:
Transmitting elements such as Bowden controls, connecting or tie rods may be provided which transmit the movement of the operating elements to the forceps jaws. It is furthermore possible that distally disposed actuators are provided which create the pivoting or bending movement. The actuators may be electrically operable micro actuators such as micro motors in particular.
It is furthermore possible to use at least one rigid pair of forceps as forceps which has a distal end adapted to be bent as a single unit and having jaw parts which are connected via a rod or the like to a proximally disposed operating element. A pair of forceps of this type is described, for instance, in the document WO 97/49342.
It is preferable to provide an equalising mechanism which prevents a variation of the relative angular position of the two jaw parts of the jaw when the distal end is bent or pivoted, respectively, as a single unit, because in such a case the tissue can neither be damaged nor slide out of the respective jaw parts when the spacing of the two forceps is varied.
In the event of application of a pair of rigid forceps it is furthermore preferable to configure the rod, in a manner known per se, for flexibility in the bending region or for closing the jaw in response to traction or pressure.
In the event of application of xe2x80x9crigid forcepsxe2x80x9d it is moreover preferable to provide an actuator and specifically a regulating screw which may be operated in a way that the distal end is bendable or pivotable, respectively.
The regulating screw may be disposed at an angle of 90xc2x0 relative to the longitudinal axis of the instrument or concentrically with the longitudinal axis of the instrument.
The handling of the inventive instrument is further facilitated if certain angular positions of the two pairs of forceps are indexed or when the regulating screw presents a catch at defined angular positions.
The most different instruments can be inserted into the additional passage:
It is possible, for instance, to insert a suturing means or a strapping means.
Specifically when distal and proximal fallopian tube remnants are to be joined with each other after the introduction of a catheter it is expedient to provide the strapping means in the form of a catheter which permits the application of a fibrinous adhesive.
The forceps jaws of the inventive instrument may be designed fundamentally in any known configuration:
It is particularly advantageous, however, to form the forceps jaws by two respective seizing jaws. These seizing jaws may be provided with teeth so that the respective tissue parts may be securely seized.
In such a design the shape of the seizing jaws may be matched with the tissue parts to be joined so that a large-area positive clamping will be achieved.
The adaptation to different operating conditions is facilitated by the provision that the forceps jaws are additionally displaceable along the direction of the longitudinal axis of the instrument relative to the instrument body. In this design each forceps jaw may be shifted independently of the other forceps jaw.
Due to the displaceability along the direction of the longitudinal axis it is possible, inter alia, to compensate the angular offset which is produced as a result of the pivoting motion. If necessary it is also possible to provide a restricted guidance for compensation of the angular offset.